JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#" class="show-modal">Кликай</a>

<div style="display: none;">
    <div class="box-modal" id="exampleModal">
        <div class="box-modal_close arcticmodal-close">закрыть</div>
        Lorem ipsum dolor sit amet, consectetur adipisicing elit. Culpa voluptates minus ad totam eaque corrupti sint error nihil harum deserunt. Optio doloremque odit a expedita eius nostrum praesentium fuga ut.
    </div>
</div>

<script src="http://arcticlab.ru/arcticmodal/js/arcticmodal/jquery.arcticmodal-0.3.min.js"></script>

CSS

.arcticmodal-overlay,
.arcticmodal-container { position: fixed; left: 0; top: 0; right: 0; bottom: 0; z-index: 1000; }
.arcticmodal-container { overflow: auto; margin: 0; padding: 0; border: 0; border-collapse: collapse; }
*:first-child+html .arcticmodal-container { height: 100% }
.arcticmodal-container_i { height: 100%; margin: 0 auto; }
.arcticmodal-container_i2 { padding: 24px; margin: 0; border: 0; vertical-align: middle; }
.arcticmodal-error { padding: 20px; border-radius: 10px; background: #000; color: #fff; }
.arcticmodal-loading { width: 80px; height: 80px; border-radius: 10px; background: #000 url(loading.gif) no-repeat 50% 50%; }
.box-modal {
    position: relative;
    width: 500px;
    padding: 16px;
    background: #fff;
    color: #3c3c3c;
    font: 14px/18px Arial, "Helvetica CY", "Nimbus Sans L", sans-serif;
    box-shadow: 0 0 0 6px rgba(153, 153, 153, .3);
    border-radius: 6px;
}
.box-modal_close { position: absolute; right: 10px; top: 6px; font-size: 11px; line-height: 15px; color: #999; cursor: pointer; }
.box-modal_close:hover { color: #666; }
html, body { height: 100%; }
body {
    background: url(http://goo.gl/50Xu6u) no-repeat;
    background-size: cover;
}
.new-bg {
    background: url(http://goo.gl/0virQo) no-repeat;
    background-size: cover;
}

.show-modal {
    font-weight: 900;
    font-size: 2em;
    color: #fff;
}

JavaScript

$('.show-modal').click(function() {
    $('#exampleModal').arcticmodal({
        beforeOpen: function(data, el) {
            $('body').addClass('new-bg');
        },
        afterClose: function(data, el) {
            $('body').removeClass('new-bg');
        }
    });
});